The first lady in 2010 will become the lead White House spokesman in an administrationwide battle against childhood obesity, taking on her first substantial role in advancing an Obama initiative. Michelle Obama said dealing with childhood obesity will be a "major" project for her second year as first lady, and she did not rule out testifying before Congress. "If it's helpful, I wouldn't say no," she said. In her first year, Mrs. Obama tried to avoid any controversy and was ultra-cautious about taking any political risks, wanting to avoid mistakes on the campaign trail that might have portrayed her as...